[PATCH] pinctrl: bcm: pinctrl-nsp-gpio: Fix setting GPIO as output

[PATCH] pinctrl: bcm: pinctrl-nsp-gpio: Fix setting GPIO as output

[Mark Tomlinson]

When setting a GPIO pin to an output, it is important to set the value
correctly before enabling the output so that a glitch is not seen on the
pin. This glitch may be very short, but can be important if this is a
reset signal.

Fixes: 8bfcbbbcabe0 ("pinctrl: nsp: add gpio-a driver support for Broadcom NSP SoC")
Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
---
 drivers/pinctrl/bcm/pinctrl-nsp-gpio.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c b/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c
index a00a42a61a90..942f04ca4868 100644
--- a/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c
+++ b/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c
@@ -289,8 +289,8 @@ static int nsp_gpio_direction_output(struct gpio_chip *gc, unsigned gpio,
 	unsigned long flags;
 
 	raw_spin_lock_irqsave(&chip->lock, flags);
-	nsp_set_bit(chip, REG, NSP_GPIO_OUT_EN, gpio, true);
 	nsp_set_bit(chip, REG, NSP_GPIO_DATA_OUT, gpio, !!(val));
+	nsp_set_bit(chip, REG, NSP_GPIO_OUT_EN, gpio, true);
 	raw_spin_unlock_irqrestore(&chip->lock, flags);
 
 	dev_dbg(chip->dev, "gpio:%u set output, value:%d\n", gpio, val);
-- 
2.29.2

Re: [PATCH] pinctrl: bcm: pinctrl-nsp-gpio: Fix setting GPIO as output

[Ray Jui]

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On 11/16/2020 3:37 PM, Mark Tomlinson wrote:
> When setting a GPIO pin to an output, it is important to set the value
> correctly before enabling the output so that a glitch is not seen on the
> pin. This glitch may be very short, but can be important if this is a
> reset signal.
> 
> Fixes: 8bfcbbbcabe0 ("pinctrl: nsp: add gpio-a driver support for Broadcom NSP SoC")
> Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
> ---
>  drivers/pinctrl/bcm/pinctrl-nsp-gpio.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c b/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c
> index a00a42a61a90..942f04ca4868 100644
> --- a/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c
> +++ b/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c
> @@ -289,8 +289,8 @@ static int nsp_gpio_direction_output(struct gpio_chip *gc, unsigned gpio,
>  	unsigned long flags;
>  
>  	raw_spin_lock_irqsave(&chip->lock, flags);
> -	nsp_set_bit(chip, REG, NSP_GPIO_OUT_EN, gpio, true);
>  	nsp_set_bit(chip, REG, NSP_GPIO_DATA_OUT, gpio, !!(val));
> +	nsp_set_bit(chip, REG, NSP_GPIO_OUT_EN, gpio, true);
>  	raw_spin_unlock_irqrestore(&chip->lock, flags);
>  
>  	dev_dbg(chip->dev, "gpio:%u set output, value:%d\n", gpio, val);
> 

The fix looks good to me. Thanks!

Acked-by: Ray Jui <ray.jui@broadcom.com>

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